The power of the zebrafish system stems from its utility as a developmental biology model combined with the ease of its genetic manipulation and experimentation. Our understanding of key genetic mechanisms of vertebrate development has been propelled by the phenotypic characterization, genetic mapping and positional cloning of induced and spontaneous mutations in zebrafish. However, the potential of this system has not been fully realized, as inefficient microsatellite-based mapping remains the primary method in the field. We propose to apply technological and computational advances of present day genomics to genetic mapping in the zebrafish system. Specifically, we propose to develop a method for rapid and accurate mapping of recessive zebrafish mutants using Next Generation Sequencing (NGS) of pooled samples. We also propose to investigate parameters of screen design and sample analysis to optimize the use of this protocol. Finally, we aim to develop methods for identification of the causal mutation among the variants discovered within the mapping interval. Application of NGS technology, complemented by specifically developed computational techniques, will provide an efficient, accurate and inexpensive method for genetic mapping in zebrafish. This approach will enable the simultaneous identification of informative genetic markers, mapping of the mutation position, and potential identification of the causal sequence change in a single experiment. The data obtained in these genomic analyses and the methods developed will be made available to the zebrafish community. Importantly, these approaches will also be widely applicable to genetic analysis of other model systems.